Generally, a wiper mounted to a wind shield glass of a vehicle serves to prevent forward visibility of a driver from being disturbed due to rain or snow present on the wind shield glass during driving of the vehicle in rain or in snow and, in addition, to wipe the wind shield glass clean. Specifically, a wiper system is mounted at a predetermined part of a chassis of the vehicle below the wind shield glass of the vehicle, and a wiper blade performs reciprocation, i.e., alternating motions, on the wind shield glass from side to side in a fan shape when the wiper blade is driven by a motor.
Such a wiper blade for wiping foreign matter off a wind shield glass of a vehicle is disclosed in Korean Patent Application No. 2005-12755, which has been filed in the name of the applicant of the present application.
The conventional wiper blade includes body springs integrally formed and having a long groove formed at middle regions of the body springs, such that a fixing coupling member is fitted in the long groove, in the longitudinal direction thereof for supporting the wiper blade, the fixing coupling member fitted in the long groove of the body springs such that a rubber is fixedly coupled to the body springs, the fixing coupling member having clip fitting grooves formed at the upper part thereof and protrusions formed at the lower part thereof such that the protrusions are fitted in fitting grooves formed at the rubber, clips fitted in the clip fitting grooves formed at the upper part of the fixing coupling member for fixing the upper sides of the body springs in a tight contact manner, the rubber having the fitting grooves, in which the protrusions of the fixing coupling member are fitted, formed at the upper part thereof, the lower part of the rubber being in tight contact with a wind shield glass of a vehicle for wiping the wind shield glass clean, and a spoiler having depressions formed at opposite sides thereof in the longitudinal direction of the body springs.
In the conventional wiper blade, however, the rubber is fixedly coupled to the body springs by the fixing coupling member, and the fixing coupling member is in tight contact with the upper sides of the body springs by the clips. As a result, the number of parts to be assembled is large, and therefore, the structure of the wiper blade is very complicated while manufacturing costs of the wiper blade are greatly increased. In addition, a process of assembling the wiper blade is also complicated in proportion to the number of parts to be assembled, with the result that assembly productivity is also deteriorated.
In order to solve the above problem, on the other hand, there has been proposed a wiper blade including a clamp, made of a plastic material, to which an adapter mounted to an arm connected to a chassis of a vehicle is detachably mounted and body springs for elastically supporting a rubber configured to wipe a wind shield glass clean, the assembly between the clamp and the body springs being achieved by mounting pins.
Meanwhile, a wiper blade serves to not only wipe rain off a wind shield glass but also remove snow from the wind shield glass. In the conventional wiper blade including the clamp made of the plastic material, the clamp has toughness and ductility lower than those of a clamp which is made of a metal material although the plastic clamp may be easily manufactured by injection molding. As a result, the conventional wiper blade does not satisfy a snow block test during development of products, and, in addition, the shape of the clamp may be deformed.
Also, when the clamp is coupled to the body springs using the mounting pins positioned between the clamp and the body springs, assembly tolerance occurs between the clamp and the body springs. As a result, the coupling between the clamp and the body springs may loosen during use of the wiper blade for a long period of time, and therefore, the wiper blade may malfunction and thus stable use of the wiper blade may not be achieved.
For a conventional clamp 130 made of a metal material as shown in FIG. 11, on the other hand, a pair of support members 133 are configured to support body springs 120 at opposite ends of the body springs 120 in the longitudinal direction of the body springs 120. As a result, the overall size of the clamp 130 is large, and therefore, material costs are increased. Also, in order for a wiper blade to be in tight contact with a wind shield glass of a vehicle, it is necessary for each of the body springs 120 to have a predetermined radius of curvature as indicated by a dashed dotted line in FIG. 12. However, the distance between the support members 133 of the conventional clamp 130, which support the body springs 120, is large. When the clamp 130 is coupled to the body springs 120, therefore, the radius of curvature of each of the body springs 120 is changed, as indicated by a solid line in FIG. 12, with the result that opposite ends of the wiper blade are not in tight contact with the wind shield glass of the vehicle, whereby the wiping performance of the wiper blade is deteriorated.